Sterile neutrinos are a well-motivated and simple dark matter (DM) candidate. However, sterile neutrino DM produced through oscillations by the Dodelson-Widrow mechanism are in tension with current $X$-ray observations. To preserve the attractive features of this scenario, self-interactions among sterile neutrinos have been proposed as a minimal extension of the production mechanism. In this...
We propose a new search strategy for higgsinos. Assuming associated production of higgsino-like pairs with a W or Z boson, we search in the missing energy plus hadronically-tagged vector boson channel. We place sensitivity limits for (HL-)LHC searches assuming (1–3.5 GeV) mass differences between the lightest neutral and charged states. We point out that using the $E_T^{\mathrm{miss}}$...
We investigate different classes of models, in which the dark matter candidate arises
as a hadronic state of dark constituent quarks, which are charged under both the new
confining dark gauge group and the standard model. Specifically, we focus on the case
of quarks in the fundamental representation of SU(N), which are heavier than the dark
QCD confinement scale. Recent literature has...
The observed dark matter relic abundance may be explained by different mechanisms,
such as thermal freeze-out/freeze-in, with one or more symmetric/asymmetric components.
In this work we investigate the role played by asymmetries in determining the
yield and nature of dark matter in non-minimal scenarios with more than one dark matter
particle. In particular, we show that the energy...
The NA62 experiment at CERN took data in 2016–2018 with the main goal of measuring the $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay. The NA62 dataset is also exploited to search for light feebly interacting particles produced in kaon decays. Searches for $K^+\rightarrow e^+ N$, $K^+ \rightarrow \mu^+ N$ and $K^+ \rightarrow \mu^+ \nu X$ decays, where N and X are massive invisible particles, are...
SND@LHC is a compact experiment proposed to exploit the high flux of energetic neutrinos of all flavours from the LHC in a hitherto unexplored pseudo-rapidity region of 7.2 < 𝜂 < 8.4, complementary to all the other experiments at the LHC. The experiment is located 480 m downstream of IP1 in the unused TI18 tunnel. The detector is composed of a hybrid system based on an 830 kg target mass of...
Searches in CMS for dark matter in final states with invisible particles recoiling against
visible states are presented. Various topologies and kinematic variables are explored,
including jet substructure as a means of tagging heavy bosons. In this talk, we focus on
the recent results obtained using the full Run-II dataset...
The presence of a non-baryonic Dark Matter (DM) component in the Universe is
inferred from the observation of its gravitational interaction. If Dark Matter
interacts weakly with the Standard Model (SM) it could be produced at the LHC. The
ATLAS Collaboration has developed a broad search program for DM candidates in final
states with large missing transverse momentum produced in association...
Collider searches for dark matter (DM) so far have mostly focussed on scenarios
where DM particles are produced in association with heavy standard model (SM)
particles or jets. However, no deviations from SM predictions have been observed.
Several recent phenomenology papers have proposed models that explore the
possibility of accessing the strongly coupled dark sector, giving rise to...
The Micromegas detectors are part of the New Small Wheel (NSW) system of the ATLAS experiment, the largest upgrade project of Phase-1. Together with sTGC detectors they provide trigger and tracking capability in the innermost station of the end-cap part of the Muon spectrometer.
The Micromegas detector of ATLAS cover an active area of about 1280 m^2, has 1024 HV channels and 2.1 M readout...
